Substrate support unit and substrate processing apparatus

A substrate processing apparatus comprising:

• a chamber having a processing space defined therein to perform plasma processing on a substrate;
• a plasma generating unit configured to generate plasma in the processing space;
• a gas supply unit configured to supply gas to the processing space;
• and
• a substrate support unit disposed in the chamber, the substrate support unit being configured to adsorb and support the substrate,
• wherein the substrate support unit comprises:
• a heater assembly comprising a plurality of heater elements;
• a bias electrode configured to receive bias power of a first frequency from a bias power supply;
• an electric circuit board electrically connected to the heater assembly, the electric circuit board being configured to control the heater assembly;
• and
• a discharge unit comprising a discharge line connected between ground and the electric circuit board and a protection module comprising surge protection components mounted on the discharge line.

A substrate support unit comprising:

• an adsorption plate provided therein with a chuck electrode configured to provide electrostatic adsorption force to a substrate supported on an upper surface thereof and a heater assembly comprising a plurality of heater elements;
• a cooling plate disposed below the adsorption plate, the cooling plate being provided therein with a coolant channel configured to allow a coolant to circulate therethrough, the cooling plate being configured to receive bias power of a first frequency;
• an insulating plate disposed below the cooling plate, the insulating plate defining a mounting space between the insulating plate and the cooling plate;
• an electric circuit board mounted in the mounting space so as to be electrically connected to the heater assembly, the electric circuit board comprising a switch module comprising switches configured to selectively supply heater power to the plurality of heater elements and a switching diode module comprising switching diodes disposed between the switch module and the plurality of heater elements and configured to prevent reverse current;
• and
• a discharge unit comprising:
• a discharge line connecting points between the switching diodes and the plurality of heater elements to ground, and
• a protection module comprising surge protection components mounted on the discharge line.